Effect of isopropyl methylphosphonofluoridate (IMPF) poisoning on selected immunological parameters of angiogenesis

Acetylcholinesterase (AChE) and cholinergic receptors play an important role in the immune system, including lymphocyte-induced angiogenesis. However, their exact role is not fully understood. The presented work tests the influence of isopropyl methylphosphonofluoridate (IMPF), an irreversible inhibitor of AChE, on selected immune parameters associated with angiogenesis in mice. The levels of VEGF, bFGF, TNF-α, and IFN-γ production were measured, together with the ability of lymphoid spleen cells to induce local GvH reaction after a single dose of IMPF.

Experiments were performed in male BALB/c mice. Acetylcholinesterase activity in erythrocytes was determined by the Ellman`s procedure. Levels of cytokines were measured in serum using standard commercial ELISA kits. Influence of IMPF intoxication upon angiogenesis was examined by the LIA test, according to the Sidky and Auerbach procedure.

The results showed a 6- and 8-fold increase in VEGF at days 1 and 7 of the experiment, respectively, as well as a decrease (at days 14 and 21 after administration), followed by a significant increase (day 1) in bFGF levels. A statistically significant decrease in the concentration of IFN-γ was observed throughout all experiments. The maximum decrease in the level of TNF-α was found at days 1 and 7 after administration of IMPF. Additionally, a significant decrease was found in the ability to form new blood vessels following IMPF administration.

This study revealed that IMPF has a significant effect on the regulation of lymphocyte-induced angiogenesis, which is related with the modulation of angiogenic and pro-inflammatory cytokines secretion. The observed differences suggest a possible derangement of certain elements of the neuronal and/or non-neuronal cholinergic system.